An introduction to Scope 1 greenhouse gas emissions

How are Scope 1 emissions defined in the GHG Protocol?

As per the GHG Protocol, all reporting organisations must disclose GHG emissions associated with their operations and categorise them as direct or indirect. Direct emissions are emissions from sources that are owned or controlled by the company. Indirect emissions occur as a consequence of the activities performed by the reporting company but the actual emissions of greenhouse gases occur at sources owned or controlled by another company. Emissions are further divided into three scopes. Direct emissions are included in scope 1, meanwhile indirect emissions are included in scope 2 and scope 3. While a company has control over its direct emissions, it has influence over its indirect emissions.

Scope 1 includes emissions resulting from activities such as the generation of electricity, heat, or steam; the manufacture or processing of chemicals and materials; the transportation of materials, products, and waste; and the uncontrolled release of gases or vapors from industrial equipment. 

There are four different types of Scope 1 emissions:

• Stationary combustion: Emissions from burning fuels in stationary equipment such as boilers, furnaces, and generators used to produce electricity, heat or steam. Example: Burning natural gas in a factory boiler to generate steam for an industrial process.
• Mobile combustion: Emissions from fuel burned in company-owned vehicles, such as cars, trucks, and vans. Example: A company car used for business travel.
• Fugitive emissions: Emissions from unintentional leaks or release of gases,  often from industrial equipment. Example: A refrigerant leak from an air conditioning unit.
• Process emissions: Emissions released directly from on-site chemical or industrial processes during manufacturing, excluding emissions resulting from fuel combustion. Example: Carbon dioxide generated during cement production or metal smelting.

What are the requirements to be followed when reporting Scope 1 GHG emissions?

The GHG Corporate Standard provides a set of requirements that organisations must follow when calculating and reporting their Scope 1 emissions:

• Consider the principles, requirements and guidance provided by the GHG Protocol Corporate Standard and GRI 305 (Emissions 2016)
• Follow the European Sustainability Reporting Standards (ESRS 1) and define any reporting boundaries as per the standard , disclosing and explaining any exclusions. To know about the different reporting boundaries, refer to our article here
• Companies must use emission factors that include the emissions of all greenhouse gases defined in the Kyoto Protocol. In Ducky, we use emission factors  compliant with this requirement
• Companies need to disclose the choice of method(s) and emission factors used for calculating Scope 1 emissions. 
• Companies should report Scope 1 emissions in tonnes of carbon dioxide equivalent (t CO₂e).

How does the GHG Protocol recommend calculating Scope 1 emissions?

The GHG Protocol recommends the following approach to calculate Scope 1 emissions:

1. Identify direct emission sources: Begin by identifying all company-owned or controlled sources that emit greenhouse gases directly by referring to the four source categories listed above. Process emissions are usually only relevant to certain industry sectors like oil and gas, aluminum, cement, etc. Manufacturing companies will likely have direct emissions from all the main source categories. Office-based organisations may have direct GHG emissions if they own or operate a vehicle, combustion, refrigeration and air-conditioning equipment.
2. Collect activity data: For each source, gather data that quantifies the activity responsible for emissions. Examples include:
   • Fuel consumption (e.g., liters of diesel used in boilers or vehicles)
   • Distance traveled (e.g., kilometers driven by company-owned vehicles)
   • Quantities of gases released during industrial processes

This data can typically be obtained from fuel purchase records, metering and monitoring systems, financial accounts, or other operational logs.

1. Apply emission factors: Multiply the activity data for each source by the appropriate emission factor, which represents the amount of greenhouse gas emitted per unit of activity (e.g., kg CO₂-equivalents per liter of diesel burned).
2. Aggregate: Sum the emissions from all identified sources to calculate total Scope 1 emissions. Report the results in tonnes of carbon dioxide equivalent (t CO₂e).

How are Scope 1 emissions calculated in Climate Reporting?

As per the GHG Protocol, Scope 1 emissions should be calculated using the activity-data method. This involves collecting activity data (fuel consumption, distance travelled, fuel spend) and applying appropriate activity-based emission factors to determine emissions. 

There are several ways to collect activity data:

• Direct consumption data: Use direct measurements of fuel consumption, typically in physical units such as kWh or MWh, obtained from meter readings or fuel bills (High accuracy).
• Estimates based on fuel spend: If measured fuel consumption data is unavailable, one can estimate fuel use by dividing the total fuel spend (from fuel bills or financial accounts) by the average price of that fuel  (Medium accuracy). 
• Estimates based on distance traveled: Estimate fuel use by multiplying total distance travelled (extracted from vehicle use logs or odometer readings) with the fuel efficiency of the vehicle (Medium accuracy). This is only applicable for mobile combustion sources (Please note that this method is not currently available in Climate Reporting).

Climate reporting currently supports Scope 1 emission calculations for stationary and mobile combustion sources only. Scope 1 emissions are calculated using the activity-based method using one of the following activity data types:

• Fuel use from direct measurement: Directly measured fuel consumption data in physical units (e.g., liters, or m³ of fuel consumed). This data must be manually entered by the user. (High accuracy)
• Fuel use from fuel spend: If directly measured fuel consumption data is unavailable, fuel use is estimated from spending on fuels (using energy bills or financial accounts). To estimate fuel use from fuel spend, the total spending on each fuel type is divided by the average fuel price of that fuel. (Medium accuracy)

After determining fuel use, the tool calculates Scope 1 emissions by multiplying the fuel use by relevant emission factors. Since the tool assumes the operational control approach for all companies, emissions from the operation of the owned or leased assets always come under Scope 1.

Who can skip this category?

Companies may exclude this category if they do not own or operate assets that can cause emissions. All other companies are required to report Scope 1 emissions, preferably using the activity-based method.